International Journal of Computer Applications (0975 – 8887) Volume 183 – No. 10, June 2021 16 Effect of Asynchronous Transfer Mode Adaptation Layers and Service Class on Network Performance Michael Asante Department of Computer Science Kwame Nkrumah University of Science and Technology Francis Kwadzo Agbenyegah Ghana Communication Technology University Department of Computer Science Kwame Nkrumah University of Science and Technology James Owusu - Kusi Department of Computer Science Kwame Nkrumah University of Science and Technology ABSTRACT This research work investigated the effect of Asynchronous Transfer Mode Adaptation Layers and Service Classes on the performance of a network. The relation between applications such as Voice, Ftp and Email, Asynchronous Transfer Mode (ATM) Adaptation Layers and ATM Service Classes and their accompanying effect on the performance of a network was investigated. Emphasis on the relation between the ATM Adaptation Layers and ATM Service Classes was centered on Email Download and Upload Response Time, Ftp Download and Upload Response Time, Voice Packet Delay Variation and Voice Packet End to End Delay. Two Scenarios were evaluated through simulations using Riverbed Modeler Academic Edition version 17.5. The results show that the type of ATM Adaptation Layer and Service Classes used for an application has an effect on the performance of a network. General Terms ATM Adaptation Layers and ATM Service Classes Keywords Email Download and Upload Response Time, Ftp Download and Upload Response Time, Voice Packet Delay Variation and Voice Packet End to End Delay 1. INTRODUCTION Computer networks has become an indispensable element of our day-to-day operations. Newer network technologies are sought after from time to time to meet the ever-increasing need of high bandwidth and low delay over long distances. To satisfy these needs, several high-speed network techniques have been developed. Networks are normally developed based on the type of data to be transported. Thus, circuit-switched networks, which included the public switched telephone network and high-speed digital transmission facilities, were primarily used to transport delay-sensitive information, such as voice and video. In comparison, on packet-based networks, such as X.25 and Frame Relay, information can tolerate a degree of delay. Network users can select a networking technology to satisfy a specific communications application, but most organizations support a mixture of applications. Thus, most organizations are forced to operate multiple networks, resulting in a degree of inefficiency and escalating communications costs. This inefficiency on the part of early network technologies to encapsulate different applications such as voice, video and data together in a single network brought to fore the creation of a new network technology by name (ATM) which by combining the features from other technologies, ATM enables a single network to support voice, data, and video. 2. PROBLEM STATEMENT Although each ATM Adaptation Layer is optimized for a specific type of traffic, there is no stipulation in the standards that ATM Adaptation Layers (AALs) designed for one class of traffic cannot be used for another. In fact, many vendors of ATM equipment currently manufacture products that use AAL5 to support all the above classes of traffic, and most activities at the ATM Forum have focused on AAL5 [11]. There is limited literature on the effect of the various types of Adaptation Layers and the applications that they transport on the performance of a network. This paper therefore investigated the effect of the various types of adaptation layers and the applications they transport and their resultant effect on network performance 3. RESEARCH OBJECTIVES The objective of this research work is to examine the effect of ATM Adaptation layers and Service Classes on network performance. The specific objectives of this research work are to: i. Examine the effect of ATM Adaptation layers and Service Classes in the transmission of Voice Application over a network. ii. Examine the effect of ATM Adaptation layers and Service Classes in the transmission of an Email document over a network. iii. Examine the effect of ATM Adaptation layers and Service Classes in the transmission of an FTP file over a network. 3.1 Research Questions The experimental setup was done to answer the following research questions RQ1: What is the effect of ATM Adaptation layers and Service Classes in the transmission of a Voice application over a network? RQ2: What is the effect of ATM Adaptation layers and Service Classes in the transmission of an Email document over a network? RQ3: What is the effect of ATM Adaptation layers and Service Classes in the transmission of an FTP file over a network?